Process for evaluating life of article subjected to thermal cycles based on comparison of strain rates measured under evaluating conditions and actual service conditions

A method to accurately evaluate a thermal cycle life of an article with a restraint rate as an evaluating parameter without providing a thermal cycle under actual service conditions to the article subjected to the thermal cycle. A thermal cycle of a temperature profile under evaluating conditions, is provided to the article, so that a temperature profile under actual service conditions and the temperature profile under the evaluating conditions satisfies the following condition expression, and the thermal cycle life of the article to be subjected to the thermal cycle under the actual service conditions is evaluated, based on the restraint rates determined in the temperature profile,|[t(x)−t0]/[t(x=i)−t0]−[T(x)−T0]/[T(x=i)−T0]|<Ewherein [t(x)−t0]/[t(x=i)−t0] is a standardized temperature profile under the actual service conditions; [T(x)−T0]/[T(x=i)−T0 is a standardized temperature profile under the evaluating conditions; and E is a predetermined value.